DIY Electric Car Forums banner

1 - 15 of 15 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter #1 (Edited)
I am finally formally starting my Mazda RX8 conversion, Project EVolution. The main aims of the project is to have a sporty electric coupé with as much range as possible from the Better Place battery pack I have. I understand there are going to be trade off’s with this.

Another aim is to document the process as much as possible and make it easier for others to follow suit. Mazda RX8's are an excellent and relatively economical donor car for a conversion. It seems more and more people are converting RX8's and I hope I can play a part in helping others have beautiful electric RX8's and save such cars with broken engines going to waste. I have gone through a lot of research so far and learned a lot from what others have shared on these forum and elsewhere which is duly and truly appreciated.

Speaking of sharing, I hope to share as much of my research, links, files, etc as possible to help others. To this end, I will set-up a dropbox which will be shared although, most if not all the folders may be read only.

A little about me, I am a Mechanical Engineer who is passionate about sustainability and renewable energy which industry I work in. I did a project on electric cars in 4th year with two other Mechanical Engineers and learned how more efficient and superior the technology is and how we could be driving such cars with the desire against the opposition from certain industries...

My uncle is also very interested in working on the project. He is modern day smith (in a long line of smiths in our family). A master craftsman, he will likely help with a lot of the major metal fabrication. He will also be chief consultant to the project having a wealth of invaluable experience.

On hearing the weight of the battery, he said straight away that the shocks will need to be upgraded. I've heard he's right! I'm thinking of getting second hand Eiback springs which are supposed to be 60% stiffer although, they are 15 mm shorter than the standard shock. These came in the RX8 PZ. Any other ideas for stiffer shocks which aren't shorter?

I presently have my favourite car, a Mazda RX8 2004 5 speed which came without the engine. It cost only €500! I got it off a man who had a race school of RX8's in Hungry. He stripped out many RX8's and even added an extra rotor to one!

I also have the battery. It is one of the Battery Place battery packs, ~24 kW h. I got it for about 10 times the cost of the car... Getting monetary matters out of the way, I'm hoping to convert around €12k mark in total. Being in Europe something similar to, http://shop.rebbl.com/3631239/diy-15...-start-up-kit- would cover most of the rest of what I needed. I won't need a throttle though as the standard throttle works with the EVNetics Soliton jr. =)

I will probably get the other parts over the course of the next few months. I am going for a DC conversion as AC is simply too expensive for me presently. If I were to go AC, it would likely be using a crashed Nissan Leaf or similar. I actually think this could be cost effective way of converting a car. I have tried looking into this but I can't seem to find anything over here in Ireland or the UK. If anyone knows better please let me know. I like options :)

As I've mentioned previously, I'm thinking of Kostov K11 Alpha for the motor and an EVNetics Solitan jr. for the motor controller. I know other RX8 conversions have similar set-ups. The reason I am thinking of an K11 Alpha is that it is one of the most powerful DC motors without going into direct drive territory or being too heavy and seems to have a very good weight to performance ratio. Any feedback on my intended choices are openly welcome positive and negative.

As for the adapter plate, I am looking into having this piece machined from CAD drawings I found online. I know this can be readily bought but it could save some money having it made and it would be nice to have some parts open source per se.

As for chargers, again, I'd like to be as open source as possible and there are options to this end but they seem a bit expensive. I'm open to advice here.

I appreciate from others experience that getting the ECU working without the engine is one of the trickier elements of the conversion. I know there is some open info on this: http://www.madox.net/blog/projects/mazda-can-bus/ but I think it will be more hassle than it is worth presently. To overcome this, I am presently looking at: Mazda RX8 ECU Replacement Module from CANbusAuto, http://www.canbusauto.co.uk/10.html. I have sent them an email and am waiting for their response.

For the this project though, the trickiest thing is going to be that I work in England and the car is in Ireland... Not ideal :/ If we didn't like challenges though, we won't convert car to electric though would we? This will naturally limit the pace of progress but as we know converting a car is marathon not a race (the races come later...).

All feedback and questions welcome. I look forward to collaborating with you all.
 

Attachments

·
Registered
Joined
·
3 Posts
Looks like its going to be a cool project! Nice find on the ECU replacement module from the CANbusAuto guys. Should be a good workaround in getting the steering, airbags etc., to work again. I'm on the lookout for an RX8 for my own project. The RX8's seem to be a decent base to start from. Best of luck with the work.
Kieran
 

·
Registered
Joined
·
2 Posts
This is a great idea. I look forward to seeing your progress. Please don't give up. I have toyed with the concept of a minimum 70 mile range with awd with a zero to sixty in the 4.0 second bracket (just for the unbeleivers...) in addition to full lighting and heating... I got as far as calculating the Ah required. When I looked at getting a reliable battery pack I ran into problems.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #5
Looks like its going to be a cool project! Nice find on the ECU replacement module from the CANbusAuto guys. Should be a good workaround in getting the steering, airbags etc., to work again. I'm on the lookout for an RX8 for my own project. The RX8's seem to be a decent base to start from. Best of luck with the work.
Kieran
Thanks Kieran,

Yeah, its going to take alot of time but really interesting and challenging!

Yeah, its great to have a tailored solution. They got back to me too by the way reasonable price I think (I'd say but prob better contact them as its semi-bespoke and takes 3 weeks).

I will share part of the response though. I don't think they'd mind that.

"We can provide a controller for either one or both the Dash and Power Steering.
To work you will need to retain all the standard factory ABS (needed for Speed input) and factory Power Steering Electronics and factory wiring for everything to work?

We have provided Steering controllers for Electric Conversions before, what dash function data does the electric conversion have (RPM, Tempo etc..)?"

That's a good question, Q1 (I'm going to number my questions so that we can all keep track ;) ) what kind of data would a motor like a Kostov K11 alpha give out?

Personally, I think its one of the best cars to start with for price, looks, availability, ease, etc.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #6
This is a great idea. I look forward to seeing your progress. Please don't give up. I have toyed with the concept of a minimum 70 mile range with awd with a zero to sixty in the 4.0 second bracket (just for the unbelievers...) in addition to full lighting and heating... I got as far as calculating the Ah required. When I looked at getting a reliable battery pack I ran into problems.
The progress will be spuradic as I'm living in a different country than the car!

I would like something like a 110 km (70 mile) range I think narrower tyres maybe needed for that and some weight saving somewhere...

0-60 times shouldn't be a problem with a DC motor and all the torque you get with that. I would like it to be zippy and show what kinda performance electrics car can give :)
 

·
Registered
Joined
·
15 Posts
Discussion Starter #7 (Edited)
Nice Project.

Where about's in England are you?

You're welcome to pop by for a drive in mine if your ever near to WR8 0LX.

Cheers,

Mike
Hi Mike,

I'm up in Newcastle a bit away.

If I'm down in that neck of the woods I'll definitely let you know! I'd love a drive of your car =) And see how you've done things.

I've looked through your thread quite a bit and learned quite a lot; big thanks for all the shared info. You've helped make it that bit easier. I intend on paying it forward.

Vincent
 

·
Registered
Joined
·
15 Posts
Discussion Starter #8
I'll give a bigger update when I have a more time with what I learned about taking out the radiator, exhaust, etc. I was very busy over Christmas worked a fair amount getting her ready for the electrical components :)

Here's a pic of the car with the battery for now though...
 

Attachments

·
Registered
Joined
·
3 Posts
Hi Vincent,
You should be able to get information like shaft rotational speed, and motor temperature from the Kostov K11 pretty easily. Quite a few people have used Kostov motors in their EV's on this site so you might be able to get more detailed information with a quick search.
The Renault battery is quite big. Are you planning on splitting the pack to get it fitting nicely in the RX8?
Kieran
 

·
Registered
Joined
·
15 Posts
Discussion Starter #10
Hi Vincent,
You should be able to get information like shaft rotational speed, and motor temperature from the Kostov K11 pretty easily. Quite a few people have used Kostov motors in their EV's on this site so you might be able to get more detailed information with a quick search.
The Renault battery is quite big. Are you planning on splitting the pack to get it fitting nicely in the RX8?
Kieran
Yes, that sort of information should be available here somewhere. I must get back to them actually its been a while since they replied. I may hold off ordering it though until I'm about to order my motor.

Yes, the battery pack is quite big alright. I'm definitely going to split it. I want to distribute the weight around the car properly. Mazda went to a lot of effort to get a 50:50 weight distribution between front and rear and I'll try and keep that as much as possible. They guy that sold it to me, who raced them fairly highlighted this point with me.

There are three rows of batteries and I'll try and keep it like that if possible. 2 rows in the back probably and one in the front. I think it might be easier to mount 2 in the front but there's going to be more weight there with the motor, controller, etc.
 

·
Registered
Joined
·
11 Posts
Hi fellow RX8 'ers

I too am well bitten with the EV bug, the acceleration , power ,torque magic . Even though you know it is max at zero it still makes me smile. Maybe it must be all those Electrons rushing past.
I have a RX8 at a very early stage ,and very much appreciate the information in your threads keep up the good work Thanks.
 

·
Registered
Joined
·
21 Posts
Great to read your plans and mission to share the RX-8 EV build instruction! I share the same wish to save those beautiful cars and bring them back on the road in even better shape and form! I will read on your progress as I'm currently preparing my own RX-8 conversion. Thank you.
 

·
Registered
Joined
·
15 Posts
Discussion Starter #13 (Edited)
Ok, so my feedback for the strip down of the Engine bay, exhaust, etc. Obviously, I had it really easy as the car didn't come with the engine so that save me a lot of effort. My tips though would be:

1. Wear protective eye wear at all times that you could get anything in your eye. I wore it along with glasses and I still got a nasty bit of rust in my eye when I was underneath cleaning rusted parts of the struts. I was ok but you don't want that sort of thing there.

Speaking of which, there's a nasty amount rust around the wheel arches, suspension system, over the heat shield for the exhaust (where it collects), etc. The car was in Scotland originally and must of been on a lot of salted roads. Not ideal, I'll have to kill the rust (diesel) and repaint properly. I could of bought a donor without such issues but I'm keeping a car on the road which is really sustainable.

2. Give the car a good power wash before you get started. Particularly underneath the car and the wheel arches. Be careful of things like wheel bearings.

3. WD40 is your friend. There was a lot of rusted screws which hadn't been touched in years. Give it a little time to work after that if its still difficult more leverage or a little tap with a hammer at the end of the wrench works nicely (particularly good for getting stuck wheel nuts off). There were a few screws which sheared off while striping the engine bay but thankfully ones that weren't needed anymore.

Now, certain screws/nuts can be particularly difficult. I got stuck getting the screws of the small radiators off. The problem was the bracket which they are mounted is really weak and so would give when you try to unscrew it. My uncle knew how to do it though :) See pic below.

Use wrenchs on the other screw to hold on to while unscrewing the first. Then reverse. Easy when you do it this way. These are big wrenches by the way. I'm lucky to have the workshop right beside a Forge/metal workshop.

4. Take off the rear bumper to take off the exhaust. I didn't but I'm pretty sure it would of been a lot easier.

Hope this helps all those people starting off RX8 conversions (there's been a lot recently which is great). I thought I'd need to give more step by step instructions of the strip down but with the manuals which are available at http://www.rotaryheads.com/PDF/RX8/.

Any questions let me know ;)
 

Attachments

·
Registered
Joined
·
15 Posts
Discussion Starter #14 (Edited)
Hi fellow RX8 'ers

I too am well bitten with the EV bug, the acceleration , power ,torque magic . Even though you know it is max at zero it still makes me smile. Maybe it must be all those Electrons rushing past.
I have a RX8 at a very early stage ,and very much appreciate the information in your threads keep up the good work Thanks.
Hi rx8spark,

Nice to hear there's a RX8 being converted in the North. Best of luck with it. If you haven't taken her apart yet my last post might be of some help.

Take easy,

Vinny
 

·
Registered
Joined
·
15 Posts
Discussion Starter #15
Great to read your plans and mission to share the RX-8 EV build instruction! I share the same wish to save those beautiful cars and bring them back on the road in even better shape and form! I will read on your progress as I'm currently preparing my own RX-8 conversion. Thank you.
Hi Friday_EV,

I'll share as much as I can. I think its in everyone's best interest to share and share alike. That's why we're here =)
 
1 - 15 of 15 Posts
Top